Dry spinning cell



March 31, 1936. H, s, EZZARD A 2,035,872

DRY SPINNING CELL Filed Dec. 15, 1934 INVENTO S QwlRYM, MA. m

ATTORNEYS.

Patented Mar. 31, 1936 UNITED STATES PATENT OFFICE DRY SPINNING CELL Application December 15, 1934, Serial No. 757,606

6 Claims.

This invention relates to spinning cells for the production of artificial silk by dry spinning, and has for its object the provision of improved means for heating spinning cells of this character. More particularly, the invention contemplates an improved dry spinning cell capable of being operated at a uniformly maintained temperature, and having means for readily adjusting and varying its operating temperature.

The spinning cell of the invention has a heating chamber thermally associated therewith and adapted to be supplied with a condensable gaseous heating medium, such for example as steam, and the operating temperature of the cell is regulated and controlled by the volume of condensed heating medium (e. g. water of condensation) accumulating and retained in the chamber. Thus, the heating chamber may be provided with appropriate means for withdrawing condensed heating medium while retaining therein a constant uniform volume of the condensed heating medium, the volume of condensed heating medium retained in the cell being conveniently adjustable to vary at will the operating temperature of the cell.

The characteristic novel features of the spinning cell of the invention may be provided in various ways, and in the single figure of the accompanying drawing, we have illustrated in elevation and partly in section one construction of spinning cell embodying these features.

The drawing illustrates a plurality of spinning cells supplied with heat from a common source and. having a common temperature regulating and controlling means. Each spinning cell comprises a tubular spinning chamber 5 surrounded throughout the greater portion of its length by a heating chamber or jacket 6. The upper end of each heating chamber 6 is connected through pipe fittings l to a steam pipe or supply header 8 which, in turn, is connected to a boiler or other source of steam from which steam of the desired dryness, pressure etc. may be obtained. The lower portions of the heating chambers 6 are connected through pipe fittings 9 to a drainage manifold II], which is cross connected to the steam supply pipe 8 through an upright pressure equalizing pipe II. The pipe II is connected to a parallel liquid discharge pipe I2 through a plurality of horizontal pipes I3, I4, I5, I6 and I I, spaced vertically along the pipes I I and I2. The horizontal pipes are provided with valves I8, I9, 20, 2I and 22.

A spinnerette 23 extends into the top of the spinning chamber of each cell. The spinning chamber of each cell is provided at its lower end with a gas inlet 24 and at its upper end with a gas outlet 25. Each cell is provided at its bottom with a filament delivery tube 26 and with upper and lower glass-covered observation ports 27.

In operating the apparatus illustrated in the drawing the temperature within the spinning chambers is capable of adjustment at will by appropriate manipulation of the valves I8, I9, 20, 2I and 22. Thus, assuming, for a particular operation, that a proper spinning chamber temperature results from maintaining the liquid condensate in the chambers 6 at the level a, the valves I8 and I9 will be closed and the valves 20, 2| and 22 will be open. Steam (or other suitable condensible gaseous heat medium) is supplied by the pipe 8 to the heating chambers 6. Steam Will condense and fill the heating chambers to the level a and excess condensate will be withdrawn from the heating chambers and discharged to waste through the pipes I5 and I2. The steam pressure in the upper part of the pipe I I prevents condensate from being siphoned or forced through the pipe I5, since this pressure is equal to the pressure on the condensate in each of the heating chambers 6. The efiective gaseous heating volume of each chamber 6 is the space above the level a of the condensate in the chambers, and since the condensate in each heating chamber is maintained at a constant and uniform level, the eifective gaseous heating volume or space is the same in each individual cell. The

eliective heating surface of the heating chambers in contact with the gaseous heating medium may be decreased, and hence the operating temperature of the cell lowered, by maintaining a higher level of condensate in the heating chambers, and similarly the operating temperature of the cells may be increased by maintaining a lower level of condensate in the heating chambers. This variation in the operating temperature of the cells is readily accomplished in the apparatus illustrated in the drawing by appropriate manipulation of the valves I8, I9, 20, 2I and 22.

Since the condensate in the heating chamber is below the steam in the chamber, the condensate cools gradually to a relatively low exit temperature because there are practically no adverse currents.

The air (or other gas) taken in at the inlet 24 is first heated by radiation from the relatively cool condensate in the bottom of the heating chamber 6, which is a relatively mild heating 50 medium, and then by the steam (or other gaseous heating medium) in the heating chamber above the level of the condensate therein. The invention thus permits very accurate control of the temperature to which the evaporating medium is heated. Furthermore, a wide range of operating temperatures is possible with great uniformity and precision from cell to cell, even when using steam as a heating medium, which otherwise would give too great heat transfer. Using steam above atmospheric pressure, the invention permits temperatures of the evaporating medium as low as 40 C. and as high as 80 C. under the same conditions of spinning, holding any temperature within this range with great uniformity in each individual cell and in all cells of the group. In addition, a greater variation in temperature may be secured by varying the pressure of the steam supplied to the heating chambers, any appropriate pressure-regulating device being employed for varying and controlling the steam pressure.

We claim:

1. In a battery having a plurality of spinning cells for the production of artificial filaments by dry spinning, an individual heating chamber thermally associated with each cell, means for admitting a condensable gaseous heating medium to each chamber, means permitting the accumulation in each chamber of condensed heating medium, means for simultaneously varying the effective heating surface of the chambers in contact with the gaseous heating medium by simultaneously varying the volume of condensed heating medium retained in each chamber, a separate conduit for withdrawing the condensed heating medium from the chambers, and means for equal izing the gaseous pressure between said conduit and the means for admitting the condensable gaseous heating medium.

2. In a spinning cell for the production of artificial filaments by dry spinning, a heating chamber thermally associated with the cell, steam admission means for said chamber, a conduit connecting said steam admission means with the bottom and the top of said chamber, and a plurality of valved outlet pipes connected to said conduit in spaced relation to one another for withdrawing liquid of condensation from said chamber.

3. An improved apparatus for the production of artificial filaments by dry spinning comprising a plurality of spinning cells, a heating chamber thermally associated with each of said cells,

means for admitting a condensable gaseous heating medium to each of said chambers, means for accumulating and retaining at a common level in each of said chambers liquid of condensation whereby each chamber has substantially the same effective heating surface in contact with the gaseous heatingmedium, a separate conduit for withdrawing the condensed heating medium from the chambers, and a pipe connecting said conduit with the gaseous heating medium admission means.

4. An improved apparatus for the production of artificial filaments by dry spinning comprising a plurality of spinning cells, a heating chamber thermally associated with each of said cells, a steam header for supplying steam to each of said chambers, a drainage manifold connected to the lower end of each of said chambers, a vertically disposed conduit connecting said header and said manifold, a plurality of outlets positioned at different levels along said conduit, and valves associated with said outlets.

5. An apparatus for producing artificial filaments by dry spinning which comprises a plurality of vertically disposed spinning cells, individual steam condensing chambers thermally associated with each of the cells, means for introducing steam into the upper end portion of each of the chambers, a condensate manifold connected to the lower end portion of each chamber, a conduit connected to the condensate manifold and to the steam introduction means, and a plurality of valved pipes connected in spaced relationship along said conduit and adapted to permit the withdrawal of condensate therethrough.

6. An apparatus for producing artificial filaments by dry spinningwhich comprises a plurality of elongated vertically disposed spinning cells each provided with an annular steam jacket, a steam inlet manifold connected to the top of each jacket, a condensate outlet manifold connected to the bottom of each jacket, a conduit connected to the inlet manifold and the outlet manifold, and a plurality of valved outlet pipes connected to said conduit at different levels;

HENRY SPEER EZZARD. ERNEST CHARLES KONTZ, JR. 

